Cosmological Fast Radio Bursts from Binary White Dwarf Mergers
Kunihito Ioka (KEK)
Kashiyama, KI & Mészáros 13 ~10年前 GRB Cosmology Massive star origin ⇒ High redshift GRBs
Like QSO Like SN Star formation Reionization Metal, Dust ? Dark energy … z~10-30 Larson & Bromm 02 GRB GRBs are useful z~8 for13/11/14 probing high-z Fast Radio Burst by K. Ioka (KEK)QSO, galaxy 2 Radio Dispersion In a plasma, a light signal High energy photon is delayed 2 2 2 2 ! = k c +! p plasma frequency 2 4"ne 4 1 2 1 Low energy photon ! = = 5.63!10 n s" p m Ionized region (2 " ! % " DM % Luminosity !t = 4.15 s $ ' $ ' #1 GHz & #103 pc cm(3 & Distortion in light curve ⇒ DM t~Δt Time 13/11/14 Fast Radio Burst by K. Ioka (KEK)⇒ Reionization History3 Dispersion Measure is the column density of free electrons along light path Dispersion Measure Dispersion Measure ↓ Reionization History Reionization Recombined electrons redshift provide no DM
13/11/14 Redshift Fast Radio Burst by K. Ioka (KEK) KI 03, Inoue 04 4 Intergalactic DM
DMIGP including missing baryon 3 -3 DMGalaxy~30-10 pc cm KI 03
13/11/14 Fast Radio Burst by K. Ioka (KEK) 5 DM from Afterglow Distortion at t~Δt ⇒ DM Δt∝ν-2 Unfortunately radio afterglows
KI 0313/11/14 Fast Radio Burst by K. Ioka (KEK) are not so bright6 Fast Radio Bursts Thornton+ 13
64m Parkes radio telescope (New South Wales) High Time Resolution Universe (HTRU) Survey High latitude survey (-70 deg < b < -30 deg) ν=1.382 GHz, Δν=400 MHz/1024, Δθ~14 arcmin F=0.6-8.0 Jy ms !!! Most luminous radio transients 13/11/14 Fast Radio Burst by K. Ioka (KEK)if cosmological 7 Dispersion Measure Thornton+ 13
Lorimer Burst
δt∝DM・ν-2 Galactic latitude DM=500-1000 cm-3 pc 13/11/14 Fast Radio Burst by K. Ioka (KEK) 8 Summary of FRB Obs.
-3 DM=500-1000 cm pc (z=0.5-1, dL~2-6Gpc) 38-40 Sν~Jy ⇒ Eiso~10 erg δt=5.6ms,<4.3,1.4,1.1ms ⇒ cδt(1+z)-1 < 1500(1+z)-1 km Rate~(1±0.5)×104/sky/day~10-3/yr/galaxy ⇔ Supernova rate 10-2/yr/galaxy No repeated bursts so far No counterparts so far
13/11/14 Fast Radio Burst by K. Ioka (KEK) 9 Hassall+ 13 Expected Rate Lorimer+ 13 Trott+ 13 Low frequency component SKA1 could find an extragalactic burst every hour
1 event/hour
13/11/14 Fast Radio Burst by K. Ioka (KEK) 10 Less turbulent
Lorimer+ 13
13/11/14 Fast Radio Burst by K. Ioka (KEK) 11 Possible Origins
RRAT (Rotating Radio Transient; intermittent pulsar) Giant pulse from a msec/young pulsar Evaporation of BH Rees 77; Blandford 77; Kavic+ 08; Keane+ 12
SN into a nearby star Colgate+ 71,75; Egorov & Postnov 09 Magnetar giant flare Popov & Postnov 07; Thornton+ 13 Collapse of hypermassive NS Falcke & Rezzolla 13; Zhang 13 Binary NS mergers Hansen & Lyutikov 01; Totani 13 Superconducting cosmic strings Cai+ 12 Nearby flaring stars Loeb+ 12 13/11/14 Fast Radio Burst by K. Ioka (KEK) 12 Binary White Dwarf Mergers? Kashiyama, KI & Meszaros 13
Massive WD SN Ia Short GRB via →NS WD pulsar CR e± excess Kashiyama+ 11 GW sources
13/11/14 Fast Radio Burst by K. Ioka (KEK) FRB? 13 Minimum Requirements Energetics Timescale Event rate
13/11/14 Fast Radio Burst by K. Ioka (KEK) 14 Energetics
9 Magnetic Energy Bobs,max~10 G 2 3 B 4!r 43 2 3 E ! " ~ 2 "10 erg B r B 8! 3 9 8.7 WD-WD merger ⇒ Differential rotation ⇒ B GM 2 E ! ! 1050 erg max r v ! " ~ 1 s#1r#3 2 r 8.7 13/11/14 Fast Radio Burst by K. Ioka (KEK) 15 Loren-Aguilar+ 09, Ji+ 13 Timescale WD radius !1 !1 c!t(1+ z) "1.5#108 (1+ z) cm < 108.7cm 1 2 # r"& rcap ! r% ( $ c ' 7 3 2 1 2 ~ 6.7)10 cm r8.7 "0 r cap ~ 2.3 ms r3 2!1 2 c 8.7 0
13/11/14 Fast Radio Burst by K. Ioka (KEK) 16 Event Rate WD-WD merger rate !2 !3 !1 !1 RWD2 ~ 10 !10 yr galaxy
~4000 WDs in SDSS Radial velocity ⇒ Binary fraction & distribution n(a)∝aα
Badenes & Maoz 12
13/11/14 Fast Radio Burst by K. Ioka (KEK) 17 Binary White Dwarf Mergers? Kashiyama, KI & Meszaros 13
Energetics 40 EB~10 erg Timescale
rcap/c~ms Event rate ~SN Ia SN Ia as a counterpart? 13/11/14 Fast Radio Burst by K. Ioka (KEK) 18 Counterparts
Supernova Ia (Double degenerate model) 47 X-ray debris disk LX<10 erg/s for ~100sec Swift for nearby FRBs
19 13/11/14 Fast Radio Burst by K. Loren-Aguilar+Ioka 09, (KEK) recently Beloborodov 13 KI 03 FRB Cosmology McQuinn 13 Reionization Missing baryon Dark energy, cosmological parameters
z 3cH0!b (1+ z)dz DMIGP = ' 0 3 1 2 8!Gmp # 1 z % $!m ( + ) +!" & Fast radio bursts c(1+ z) z dz dL = ' 0 3 1 2 as cosmological tools H0 # 1 z % $!m ( + ) +!" & 13/11/14 Fast Radio Burst by K. Ioka (KEK)New frontier? 20 Spin Down Luminosity 2 6 4 B r " 38 1 2 6 4 L ! ~ 1.7#10 erg s$ B r " <<1043 erg/s spin c3 9 8.7 0 B reconnection ⇒ FRB like solar flares, magnetar flares
13/11/14 Fast Radio Burst by K. Ioka (KEK) 21 Acceleration 2 3 B# r 16 2 3 ! " ~ 2.5$10 Volt B # r max 2c2 9 0 8.7 ⇒ e± production ⇒ Coherent radio emission
13/11/14 Fast Radio Burst by K. Ioka (KEK) 22 Beaming Kashiyama, KI & Meszaros 13
Injection ≠ Emission
13/11/14 Fast Radio Burst by K. Ioka (KEK) 23 Brightness Temperature "r2 2! 2 F = ! kT ! d 2 c2
41 "2 T ~ 3!10 K L43remi,10 ⇒ Coherent emission
2 2 P~|E| ~|E1+E2+E3+…+EN| 2 ~N|E1| (incoherent) ~N2|E |2 (coherent) 13/11/14 1 Fast Radio Burst by K. Ioka (KEK) 24 Curvature Radiation
3 3c !c ! " 4#rc 3 "1 ~ 0.72 GHz "3rc,10
1 3 1 3 ! !1100" 9 rc,10
13/11/14 Fast Radio Burst by K. Ioka (KEK) 25 Luminosity 2 Ltot ! (Pc Ncoh )" Npat 4 2 2! e c "17 "1 4 "2 Pc ~ 2 ~ 5!10 erg s !3 rc,10 3rc
4 2 c 16 3 "5 2 Ncoh # ne !Vcoh # ne ! 2 remi ~ ne ! 2 !10 cm !3 rc,10remi,10 ! "c
Vemi 1 2 1 28 3 2 Npat # # 4# fremi$remi ~ ! 9 !10 cm fremi,10$remi,7.8 Vcoh Vcoh Vcoh
42 "1 2 "1 "1 4 Ltot ~ 4 !10 erg s fne,7!3 rc,10remi,10"remi,7.8 13/11/14 Fast Radio Burst by K. Ioka (KEK) 26 Electron Density
7 1 2 1 2 1 2 "2 "1 2 ne ~ 2 !10 cm L43!3 rc,10remi,10"remi,7.8 Necessary multiplicity
ne ne 3 #1 #1 !GJ = = ~ 8"10 ne,7Bemi,5!0 nGJ Bemi! 2"ce Plasma frequency limit 1 2 $ 2 ' " 4#ne#e ne !c ! ! p " & ) , ne# = 2# % me ( " 7 ,3 5 ,2 27 13/11/14ne * 0.6 +10 cFast Radio Burst by K. Ioka (KEK)m "3 rc,10 Melrose 71 Wilson & Rees 78 Induced Compton Lyubarsky 08
Compton scattering is enhanced by photons To evade the induced Compton 3 14 3 14 3 14 ! ! 2000 rc,10 remi,10ne,7
13/11/14 Fast Radio Burst by K. Ioka (KEK) 28 Summary
Fast Radio Burst Thornton+ 13 Dispersion Measure ⇒ Cosmological? KI 03 Binary White Dwarf Merger – Energetics ✔, Timescale ✔, Event Rate ✔ – SN Ia, X-ray debris disk Kashiyama, KI & Mészáros 13 FRB Cosmology Huge occupation # ⇒ BEC?
13/11/14 Fast Radio Burst by K. Ioka (KEK) 29 Thank You Locating Missing Baryon
13/11/14 Fast Radio Burst by K. Ioka (KEK) McQuinn 13 31 Dispersion Measure
δt∝DM・ν-2 W∝ν-4 (scattered by turbulence) FRB 110220: α=-2.003±0.006, β=-4.0±0.4 FRB 110703: α=-2.000±0.006 FRB 110627: low S/N FRB 120127: low S/N -3 DM=500-100013/11/14 Fast Radio Burst by K. Ioka (KEK) cm pc 32 250
125
63 Cordes & Lazio 02 31
13/11/14 Fast Radio Burst by K. Ioka (KEK) 33 Cordes & Lazio 02
13/11/14 Fast Radio Burst by K. Ioka (KEK) 34 Host galaxy
• Galactic center DM>700 cm-3 pc
– W ∝ DbsDos/(Dbs+Dos)2
– If Dbs<
13/11/14 Fast Radio Burst by K. Ioka (KEK) 35 Spectral index is difficult to infer due to position uncertainties
13/11/14 Fast Radio Burst by K. Ioka (KEK) 36 Lorimer Burst 010724 Lorimer+ 07
LMC(Hα, HI)
S=30±10Jy, δt<5ms DM=375 cm-3 pc ⇒ z~0.1-0.3 W∝f-4.8±0.4, S∝f-4 13/11/14 b=-41.8degFast Radio Burst by K. Ioka (KEK) 37 Similar Events?
J1852-08 (FRB 010621) DM=746 cm-3 pc Keane+ 12 GRB100704A Bannister+ 12 400mJy,13/11/14 7.8ms Fast Radio Burst by K. Ioka (KEK)Rubio-Herrera+ 13 GRB101011A38 Terrestrial?
16 “Perytons” in all 13 telescope receivers
Burke-Spolaor+ 11
13/11/14 Fast Radio Burst by K. Ioka (KEK) 39 Not Terrestrial?
• Perytons have symmetric W>20 msec which is larger than 4 FRBs by >3 • FRB 110220 has an exponential tail • Perytons have DM~375 cm-3 pc < DM~500-1000 cm-3 pc for 4 FRBs • 4 FRBs are only detected in a single beam
13/11/14 Fast Radio Burst by K. Ioka (KEK) 40 Event Rate
• Observing 4078 deg2 (0.098 sky) for 270 sec +0.6 4 ⇒ RFRB(F~3 Jy ms)=1.0 -0.5×10 /sky/day • Lorimer burst FRB 010724 ⇒ R(F~150 Jy ms)=225/sky/day consistent with N∝F-3/2 -3 • RFRB~10 /yr/galaxy Huge! -2 c.f. RCCSN~10 /yr/galaxy -5 RNS2~RGRB~10 /yr/galaxy
13/11/14 Fast Radio Burst by K. Ioka (KEK) 41 Expected Rate
Surveys at 150 MHz with 30 deg2 fields of view Lorimer+ 13 could detect one source per hour above 30 Jy 13/11/14 Fast Radio Burst by K. Ioka (KEK) 42 Expected Rate
13/11/14 Fast Radio Burst by K. Ioka (KEK)Murchison Widefield Array, Trott+43 13 WD Magnetic Field
Mt. Stromlo Observatory Kawka+ 07 H-rich DA WD 13/11/14 Zeeman splittingFast Radio Burst by K. Ioka (KEK) 44 WD Magnetic Field
H atomosphere WD SDSS DR7 Zeeman splitting
Kepler+ 13 13/11/14 Fast Radio Burst by K. Ioka (KEK) 45 Magnetized Massive WD
13/11/14 Fast Radio Burst by K. Ioka (KEK) 46 Kawka+ 07; Kepler+ 13; Liebert+ 03 Double Degenerate
• Magnetized Massive WD • SN Ia • Collapse into NS and short GRB • WD pulsar – GeV-TeV e± • Gravitational wave for LISA and DECIGO • Today, Fast Radio Bursts
13/11/14 Fast Radio Burst by K. Ioka (KEK) 47 B Field Amplification
13/11/14 Fast Radio Burst by K. Ioka (KEK) Ji+ 13 48 Summary
• Fast Radio Bursts • WD-WD mergers? • Physical condition – Huge occupation # ⇒ BEC?, Properties? • Cosmology
13/11/14 Fast Radio Burst by K. Ioka (KEK) 49 13/11/14 Fast Radio Burst by K. Ioka (KEK) 50 13/11/14 Fast Radio Burst by K. Ioka (KEK) 51 13/11/14 Fast Radio Burst by K. Ioka (KEK) 52 13/11/14 Fast Radio Burst by K. Ioka (KEK) 53 13/11/14 Fast Radio Burst by K. Ioka (KEK) 54 Mass Ejection @NS Merger
13/11/14 Fast Radio Burst by K. Ioka (KEK) Hotokezaka+ 13 55